I can't resist contributing my 2 cents' worth to the lore on lens cleaning.

I believe this came mostly from excellent techs from Leitz --
it's mostly for cleaning small bits of oil and other
contaminants from "dry" lenses, but also works on oil lenses.
I keep a small vial of pure xylene on my shelf, and
a box of wooden q-tips in the drawer.  After removing
dust by blowing with a bulb, and removing water-soluble
material with breath condensed on the lens, the q-tip
is moistened with a drop of xylene and swirled on the lens
surface, which is then quickly dried and cleaned by swirling
the opposite, clean, end.  For an oil lens, wipe gently
first with absorbent (clean, non-abrasive, lint-free) paper,
then clean with the xylene-moistened wooden q-tip.  This
method works well even for highly corrected lenses with
deep concavities on their front surfaces.  To check for
completeness of cleaning, look at the lens surface using
an ocular as a magnifier and catching the reflection of
a light source.  It is important not to use plastic q-tips.
Another tip --  the optimum lens paper is the cheapest grade
of toilet paper.  Lint-free, soft, and unlimited in supply.
Expensive toilet paper contains oil.

Hal Hawkins, UTMB Galveston

-----Original Message-----
From: jim [mailto:jim@proscitech.com.au]
Sent: Thursday, January 20, 2000 10:36 PM
To: 'Gayle Callis'; histonet@pathology.swmed.edu
Subject: RE: oil immersion lens cleaning


I love these free-reigning discussions with lots of assertions. Here are
mine:

I suspect there are a few don'ts for cleaning those lenses and the rest does

not matter.

Pouring xylene all over the lenses and using abrasive papers are no-nos.

Lens paper works, but is less absorbent than Kimwipes are. A few years ago
the
local university's microscope maintainer returned from a "study tour" from
Zeiss and reported that they were using Kimwipes. Kimwipes are low lint and
contain no hard particles. Cotton can retain bits of silica from the soil
since
its a natural product.

Another correspondent asserted that cleaning oil off lenses frequently is
most
important? Maybe it is, but why? The oil is essentially non-drying. The oil
immersion lens is only ever used with oil. The oil does not attack the
cement.
It seems to me that the cleaning (other than wiping off excess oil prior to
applying a new drop) is not required, it does not improve resolution and the

process could cause damage. Why clean frequently; please give reasons!

I claim no conflict: PST sells Kimwipes and Lens Tissue!
Cheers
Jim Darley
ProSciTech                 Microscopy PLUS
PO Box 111, Thuringowa  QLD  4817  Australia
Ph +61 7 4774 0370  Fax:+61 7 4789 2313  service@proscitech.com
Great microscopy catalogue, 500 Links, MSDS, User Notes
                      www.proscitech.com

On Saturday, January 12, 1980 12:47 AM, Gayle Callis
[SMTP:uvsgc@msu.oscs.montana.edu] wrote:
> We wipe all oil off with a LENS paper, never use Kimwipes.  Then a light
> drop of xylene on lens paper, rewipe objective, dry with more lens paper,
> and if there is some residual goo,  use only a special liquid camera lens
> cleaner, so as to not damage the special coatings on lenses, objectives.
> Local camera shop had the special cleaner.
>
> I am not sure Kimwipes will not work, but was told not to use them
although
> I know my chemist husband used them on pricey quartz cuvettes for very
high
> powered UV spectroscopy work, without any scratching problems.  Funny
> thing, you can use them for eyeglasses, cuvettes, but they sure sandpaper
a
> nose!
>
> Someone in the microscope business hopefully will tell us the yeas and
nays
> of kimwipes???  Arise!
>
> Gayle Callis